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yesterday before the weather turned to ____ I saw a little white butterfly flitting along the way. It looked a lot like the little cabbage white that is very common around here. My friend at the garden center said they are a big problem and he sold me some white cloth like material (very thin)with a name I can't remember. My questions are when do I cover the kale and broccoli, do I leave it on all the time, do I water through it and what works best to secure it ?

cover it now. You can remove for watering if you want, but put the cover back on asap. Those pesky moths lay eggs and the caterpillars will eat like crazy. You can make a little frame to lay your cloth on, just fully enclose your plant. The moths will find a way in if possible. Search here in the upper left for "frames" etc and you'll see some neat ideas. I personally make self standing frames of hardware cloth (ie rabbit wire) and it works pretty well. Good luck!

@Lov2grow wrote:Do you need to keep the row cover on kale the whole time it's in the ground? i.e. seed to last harvest?

It really depends upon the life cycle of the cabbage moth worm and if you want to hand pick them or not. I typically cover my kale when it is small and ultimately take off the row cover later in the season because the plants have grown about 18" or so. Daily inspection and hand picking works well, also Bt can help in conjunction with hand picking. Organic Cabbage Worm Control

I keep mine covered transplant to frost. The plants can get pretty tall and that's why I divert from Mel's teachings about scattering plants in squares all over the gardens. My brassicas, kale and anything else that doesn't need pollinating are planted in beds together so I can keep them covered. I use PVC hoops covered with tulle or REMAY over these beds.

If you are lucky enuf to have rain so you don't have to hand water, just leave on the insect barrier fabric. Rain goes thru as does most of the sunlight. I, too, put my brassicas in one or two beds so that they are easily all covered from spring til late summer or early fall.Its also great for covering strawberries against thieving birds and blueberries.Above: Clipped to bamboo stakes over my blueberry bushes. Its called Remay or Agribon and comes in very light weights against insects to heavier cover to protect against frost. A wonderful invention.

I tucked some tulle around the last surviving cabbage. I thought I had outsmarted the 2 white butterflies flitting around the garden. Wrong. The tulle touched the edges of the leaves and I think the butterflies laid eggs on the those edges. I removed the cabbage yesterday as it was crawling with the green worms and filled with droppings. I will definitely make cages that are tall enough to keep the butterfly from touching the leaves. Since I bought over 20 yards of tulle, I will use it. Otherwise, insect barrier cloth looks like it is a tighter weave and a better product against butterflies.

@sanderson wrote:I tucked some tulle around the last surviving cabbage. I thought I had outsmarted the 2 white butterflies flitting around the garden. Wrong. The tulle touched the edges of the leaves and I think the butterflies laid eggs on the those edges. I removed the cabbage yesterday as it was crawling with the green worms and filled with droppings. I will definitely make cages that are tall enough to keep the butterfly from touching the leaves.

After I discovered that the cabbage moth had laid pale yellow conical eggs on the bottoms of the leaves of my 1" tall kale seedlings, my wife suggested covering the trays with those square umbrellas made of tulle that keep flies off of your picnic food. We found them at our local dollar store. Works like a charm!

Didn't start my kale from seeds this year but picked up transplants at a box store and discovered within a week of their being here - lots of green caterpillars chomping on the leaves.

The eggs of the cabbage butterflies were picked up at the store because the transplants were outside. My bad! Should have thought of that possibility - but didn't. I've kept the plants on a screened porch since I bought them so the butterflies couldn't get to them.

Am in the process of making screened cages for when I set them out but your ideas of tulle or the insect barrier cloths make a lot more sense and are so quicker.

@sanderson wrote:Judy, Just make sure the cage is large enough to enclose AND not let the leaves touch the tulle. The butterflies laid eggs on my cabbage leaves that touched the tulle!

I hVe never had this problem of eggs being laid through small mesh tulle...

Nor had I, UNTIL this year. I had mine all wrapped up as usual and even sprayed with BT before I went away for a week. Came back to lacey kale and collards. The plants were big enough to touch the sides of the tulle.

@sanderson wrote:Judy, Just make sure the cage is large enough to enclose AND not let the leaves touch the tulle. The butterflies laid eggs on my cabbage leaves that touched the tulle!

I hVe never had this problem of eggs being laid through small mesh tulle...

Nor had I, UNTIL this year. I had mine all wrapped up as usual and even sprayed with BT before I went away for a week. Came back to lacey kale and collards. The plants were big enough to touch the sides of the tulle.

Kay

There is no one barrier that is going to be 100% effective in a chemical free garden. The gardener must be vigilant with inspection and hand picking found pests.

Most of my greens and brassicas are under this row covered tunnel made with hula hoops:

It spans 3 different boxes and used to be covered with tulle but that only lasted one year before rotting. I'm hoping this row cover will last a few years. The slugs can still get in so I sprinkle with DE.